>> reporter: indeed, dana. crews tonight are working around the clock to repair this 80-foot sink hole along lafayette creek. east bay mud crews are using heavy equipment working into the night to repair two water lines damaged in the wash out. it is all too real for the resident when she walked over and looked out from her side yard. they look directly on to the open trench and the exposed pipe. >> i just felt like that was it. because we just have to have it here. and you know everything that you worry about it. >> reporter: city officials believe that debris blocked that drainage underneath mountain view drive. and water overran the road and simply washed it away. water, gas, sewer lines are running underneath the pavement all damaged. lafayette city manager says that repairs will not be easy. it will not be cheap, and it will not be fast. the bottom line is that it will be along the ground here for a long time and mountain view drive will be closed. even with heavy equipment operating in the area, some driv